Synchronzing input sensing with display updating

ABSTRACT

A processing system configured to receive a first display control signal corresponding to a non-display update period of a display frame and a second display control signal corresponding to a display update period of the display frame. The processing system is further configured to acquire, based on receipt of the first display control signal, first resulting signals from sensor electrodes electrically connected to the sensor driver by operating the sensor electrodes for a first type of input sensing during a first period overlapping with at least a portion of the non-display update period. Further, the processing system is configured to acquire, based on receipt of the second display control signal, second resulting signals with the sensor electrodes by operating the sensor electrodes for a second type of input sensing during a second period overlapping with at least a portion of the display update period.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional patentapplication Ser. No. 62/964,511, filed Jan. 22, 2020, which is herebyincorporated herein by reference.

BACKGROUND Field

The disclosure herein is generally related to electronic devices, andmore specifically, to operating sensing devices.

Description of the Related Art

Input devices including proximity sensor devices may be used in avariety of electronic systems. A proximity sensor device may include asensing region, demarked by a surface, in which the proximity sensordevice determines the presence, location, force and/or motion of one ormore input objects. Proximity sensor devices may be used to provideinterfaces for the electronic system. For example, proximity sensordevices may be used as input devices for larger computing systems, suchas touchpads integrated in, or peripheral to, notebook or desktopcomputers. Proximity sensor devices may also often be used in othercomputing systems, such as touch screens integrated in cellular phonesand multimedia entertainment systems of automobiles and the like.

SUMMARY

In one example, a processing system comprises a sensor device. Thesensor device is configured to receive a first display control signalcorresponding to a non-display update period of a display frame and asecond display control signal corresponding to a display update periodof the display frame. The sensor device is further configured toacquire, based on receipt of the first display control signal, firstresulting signals from sensor electrodes electrically connected to thesensor driver by operating the sensor electrodes for a first type ofinput sensing during a first period. The first period overlaps with atleast a portion of the non-display update period. Further, the sensordriver is configured to acquire, based on receipt of the second displaycontrol signal, second resulting signals with the sensor electrodes byoperating the sensor electrodes for a second type of input sensingduring a second period. The second period overlaps with at least aportion of the display update period. The second type of input sensingdiffers from the first type of input sensing.

In one example, a method for input sensing comprises receiving, at asensor driver, a first display control signal corresponding to anon-display update period of a display frame and a second displaycontrol signal corresponding to a display update period of the displayframe. The method further comprises acquiring, based on receipt of thefirst display control signal, first resulting signals with sensorelectrodes by operating the sensor electrodes for a first type of inputsensing during a first period. The first period overlaps with at least aportion of the non-display update period. Further, the method comprisesacquiring, based on receipt of the second display control signal, secondresulting signals with the sensor electrodes by operating the sensorelectrodes for a second type of input sensing during a second period.The second period overlaps with at least a portion of the display updateperiod. The second type of input sensing differs from the first type ofinput sensing.

In one example, an input device comprises sensor electrodes, and aprocessing system electrically connected to the sensor electrodes. Theprocessing system is configured to receive a first display controlsignal corresponding to a non-display update period of a display frameand a second display control signal corresponding to a display updateperiod of the display frame. The processing system is further configuredto acquire, based on receipt of the first display control signal, firstresulting signals with the sensor electrodes by operating the sensorelectrodes for a first type of input sensing during a first period. Thefirst period overlaps with at least a portion of the non-display updateperiod. Further, the processing system is configured to acquire, basedon receipt of the second display control signal, second resultingsignals with the sensor electrodes by operating the sensor electrodesfor a second type of input sensing during a second period. The secondperiod overlaps with at least a portion of the display update period.The second type of input sensing differs from the first type of inputsensing.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlyexemplary embodiments, and are therefore not to be considered limitingof inventive scope, as the disclosure may admit to other equallyeffective embodiments.

FIG. 1 is a schematic block diagram of an input device, according to oneor more embodiments.

FIG. 2 is a schematic block diagram of sensor electrodes, according toone or more embodiments.

FIG. 3A is a schematic block diagram of an input device, according toone or more embodiments.

FIG. 3B illustrates a display frame, according to one or moreembodiments.

FIG. 3C illustrates a display line update period, according to one ormore embodiments.

FIG. 4 is a schematic view of a stack-up of an input device, accordingto one or more embodiments.

FIG. 5 is a flow chart illustrating a method for capacitive sensing,according one or more embodiments.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements disclosed in oneembodiment may be beneficially utilized on other embodiments withoutspecific recitation. The drawings referred to here should not beunderstood as being drawn to scale unless specifically noted. Also, thedrawings are often simplified and details or components omitted forclarity of presentation and explanation. The drawings and discussionserve to explain principles discussed below, where like designationsdenote like elements.

DETAILED DESCRIPTION

In an input device comprising both a sensing device and a displaydevice, interference generated by the display device negatively affectsthe ability of the sensing device to accurately detect input objects.For example, interference due to a display device may result in ghostinput objects (e.g., false input objects or the incorrect determinationof input objects) being reported by a sensing device. In variousexamples, display interference is mitigated by acquiring sensing dataduring periods that do not overlap with display updating as such sensingperiod are not adversely affected by display interference. The sensingdata acquired during periods when display updating is not occurring maybe utilized to mitigate the effects of display interference on thesensing data acquired while display updating is occurring.

The following detailed description is merely exemplary in nature and isnot intended to limit the disclosure or the application and uses of thedisclosure. Furthermore, there is no intention to be bound by anyexpressed or implied theory presented in the preceding background,summary, or the following detailed description.

The terms “coupled with,” along with its derivatives, and “connected to”along with its derivatives, may be used herein, including in the claims.“Coupled” or “connected” may mean one or more of the following.“Coupled” or “connected” may mean that two or more elements are indirect physical or electrical contact. However, “coupled” or “connected”may also mean that two or more elements indirectly contact each other,but yet still cooperate or interact with each other, and may mean thatone or more other elements are coupled or connected between the elementsthat are said to be coupled with or connected to each other. The term“directly coupled” or “directly connected” may mean that two or elementsare in direct contact.

FIG. 1 illustrates an input device 100, according to one or moreembodiments. The input device 100 includes a processing system 110 andsensor electrodes 120. The input device 100 is configured to provideinput data corresponding to one or more input objects to an electronicsystem.

The electronic system may be one of a personal computer (e.g., a desktopcomputers, laptop computers, or netbook computers), a tablet, a mobilephone, and e-book readers, among others. Further, the electronic systemmay be an internet of things (IoT) device. In other embodiments, theelectronic system is a multimedia controller of an automobile or othertype of vehicle. The input device 100 may be integrated within a commonhousing with the electronic system, or separate housing from theelectronic system. In one embodiment, the electronic system may bereferred to as a host device and a processor of the electronic systemmay be referred to as a host processor. The host processor may be acentral processing unit (CPU), a graphics processing unit (GPU), oranother processor of the hot device. The input device 100 maycommunicate with parts of the electronic system using any combination ofwired or wireless connections. In various embodiments, the input device100 may be referred to as a touchpad, a touch screen, a touch sensordevice and the like.

The input device 100 is configured to sense input associated with one ormore input objects 140 in a sensing region of the input device 100.Example input objects 140 include fingers, electrical transmitters, andpassive pens, among others, as shown in FIG. 1. Electrical transmittersmay include devices that are external to the input device 100 and thatare configured to transmit active device signals. Example electricaltransmitters may include active pens, among others. The sensing regionof the input device 100 encompasses any space above, around, in and/ornear the input device 100 in which the input device 100 is able todetect user input, e.g., user input provided by one or more inputobjects 140. In some embodiments, the sensing region extends from asurface of the input device 100 in one or more directions into spaceuntil signal-to-noise ratios prevent sufficiently accurate objectdetection. The distance to which this sensing region extends in aparticular direction, in various embodiments, may be on the order ofless than a millimeter, millimeters, centimeters, or more, and may varysignificantly with the type of sensing technology used and the accuracydesired. Thus, an input object 140 not in contact with any surfaces ofthe input device 100 may be in the sensing region and detected by theinput device 100 and/or an input object 140 in contact with an inputsurface (e.g., touch surface) may be in the sensing region and detectedby the input device 100. The input surface may be provided via a facesheet or a lens disposed over the sensor electrodes.

The processing system 110 comprises sensor circuitry 112. The sensorcircuitry 112 is configured to operate the sensor electrodes 120 forcapacitive sensing. For example, the sensor circuitry 112 is configuredto drive the sensor electrode 120 with sensing signals and receiveresulting signals from the sensor electrodes 120 for capacitive sensing.For example, in one embodiment, the sensor circuitry 112 includestransmitter circuitry configured to drive one or more of the sensorelectrodes 120 for capacitive sensing to acquire resulting signals fromone or more of the sensor electrodes 120. The transmitter circuitry mayinclude driver circuitry and/or amplifier circuitry, among others.Further, the sensor circuitry 112 includes receiver circuitry configuredto receive resulting signals from the sensor electrodes 120. Thereceiver circuitry may include one or more of analog front ends (AFEs),filter circuitry, sample and hold circuitry, analog to digital converter(ADC) circuitry, and/or demodulation circuitry, among others.

In one embodiment, the sensor circuitry 112 operates the sensorelectrodes 120 for different types of sensing. For example, the sensorcircuitry 112 operates the sensor electrodes 120 for transcapacitivesensing, absolute capacitive sensing, and/or active device (e.g., activepen) sensing.

In embodiments where the sensor circuitry 112 operates the sensorelectrodes 120 for transcapacitive sensing (e.g., in a transcapacitivesensing mode), the sensor circuitry 112 may be configured to drive afirst one or more of the sensor electrodes 120 with a transcapacitivesensing signal and receive resulting signals from a second one or moreof the sensor electrodes 120. The resulting signals may comprise effectscorresponding to the transcapacitive sensing signal. The sensorelectrodes that are driven with the transcapacitive signal are modulatedrelative to the sensor electrodes that operated to receive the resultingsignals. In one embodiment, the sensor electrodes that receive theresulting signals may be held at a substantially constant voltage ormodulated different (e.g., different frequency, amplitude, and/or phase)from that of the sensor electrodes driven with the transcapacitivesensing signal.

The transcapacitive sensing signal has a varying voltage and is aperiodic or aperiodic signal. Further, the transcapacitive sensingsignal may be one of a square waveform, a sinusoidal waveform, atrapezoidal waveform, and a triangular waveform, among others. Thetranscapacitive sensing signal varies between two or more voltages. Forexample, the transcapacitive sensing signal may vary between a firstvoltage and a second voltage, where the second voltage is greater thanthe first voltage. In one embodiment, the first voltage may be in arange of about 0 V to about 5 V and the second voltage may in a range ofabout 5 V to about 10 V. However, in other embodiments, other voltagesmay be utilized. Further, the frequency of the transcapacitive sensingsignal may be in a range of about 100 kHz to about 1 MHz. However,frequencies less than about 100 kHz and greater than about 1 MHz may beutilized.

In a transcapacitive sensing mode, the input object 140 affects thecapacitive coupling (e.g., the transcapacitance) between two or more ofthe sensor electrodes 120. For example, the input object 140 may reducethe capacitive coupling between a sensor electrode driven with atranscapacitive sensing signal and one or more sensor electrodesoperated to receive a resulting signal. The effects of the capacitanceof the sensor electrode is reflected in the resulting signal.

In embodiments where the sensor circuitry 112 operates the sensorelectrodes 120 for absolute capacitive sensing (e.g., in an absolutecapacitive mode), the sensor circuitry 112 is configured to drive one ormore of the sensor electrodes 120 with an absolute capacitive sensingsignal and receive resulting signals from the driven sensor electrode orelectrodes. The resulting signals comprise effects corresponding to theabsolute capacitive sensing signal. Driving the sensor electrodes 120with the absolute capacitive sensing signal comprises modulating thesensor electrodes 120 relative to a system ground of the input device100. Further, driving the sensor electrodes 120 with the absolutecapacitive sensing signal comprises modulating the sensor electrodes 120relative to the input object 140.

The absolute capacitive sensing signal has a varying voltage and is aperiodic or an aperiodic signal. Further, the absolute capacitivesensing signal may comprise one of a square waveform, sinusoidalwaveform, trapezoidal waveform, and triangular waveform, among others.Further, the absolute capacitive sensing signal may vary between two ormore voltages. In one embodiment, the absolute capacitive sensing signalvaries between a first voltage and a second voltage. The first voltagemay be in a range of about 0 V to about 5 V and the second voltage maybe in a range of about 5 V to about 10 V. However, in other embodiments,other voltages may be used. In one or more embodiments, the absolutecapacitive sensing signal has a frequency in a range of about 1 kHz toabout 1 MHz. However, in other embodiments, frequencies of less thanabout 1 kHz or frequencies above 1 MHz may be utilized.

In an absolute capacitive sensing mode, the input object 140 affects theabsolute capacitance of a sensor electrode 120 driven with an absolutecapacitive sensing signal. For example, the input object 140 mayincrease the capacitance of the sensor electrode 120 driven with anabsolute capacitive sensing signal. The effects of the capacitance ofthe sensor electrode 120 is reflected in the resulting signal.

The sensor circuitry 112 may operate one or more sensor electrodes 120for transcapacitive sensing and absolute capacitive sensing. Forexample, the sensor circuitry 112 is configured to receive a resultingsignal from a sensor electrode driven with a transcapacitive sensingsignal. Additionally, the sensor circuitry 112 modulates a sensorelectrode utilized to receive a resulting signal during transcapacitivesensing with an absolute capacitive sensing signal. In such anembodiment, the resulting signal comprises effects corresponding to thetranscapacitive sensing signal and the absolute capacitive sensingsignal. Further, in such embodiments, the absolute capacitive sensingsignal differs from the transcapacitive sensing signal. For example, oneor more of the waveform, frequency, amplitude, and phase of the absolutecapacitive sensing differs from that of the transcapacitive sensingsignal.

The sensor circuitry 112 operates the sensor electrodes 120 in an activedevice sensing mode to acquire an active device signal to detect anactive device. In such embodiments, the input object 140 is an activedevice external to the input device 100 and transmits a signal to beacquired by the sensor circuitry 112 with the sensor electrodes 120. Forexample, the active device may be an active pen configured to transmitan active pen signal. The active device sensing mode may be referred toas an active pen sensing mode. Further, throughout the followingdisclosure where references are made to active pens, other activedevices may be referenced instead.

The sensor circuitry 112 operates the sensor electrodes 120 to acquire aresulting signal comprising effects corresponding to an active pensignal from the input object 140. For example, the sensor circuitry 112may hold one or more of the sensor electrodes 120 at a substantiallyconstant voltage to receive a resulting signal that corresponds to theactive pen signal.

The active pen signal is generated by a crystal oscillator disposedinside the active pen, although other mechanisms for generating signalsmay be used. The active pen signal has waveform parameters (e.g.,frequency, amplitude, phase, etc.) which are predetermined and known bythe input device 100. However, in other embodiments, the active pensignal has a waveform parameter that is unknown by the input device 100.The active pen signal is generated by the input object 140 external tothe processing system 110. As such, one or more of the parameters of theactive pens signal is unknown by the processing system 110. The activepen signal may be periodic or aperiodic. Further, the active pen signalmay have a square waveform, sinusoidal waveform, a triangular waveform,or a trapezoidal waveform, among others. Additionally, the active pensignal may vary between two or more voltages. Further, the frequency ofthe active pen signal may be in a range of about 1 kHz to about 1 MHz.However, in other embodiments, the frequency of the active pen signalmay be less about 1 kHz or greater than about 1 MHz. The active pensignal differs from that of the absolute capacitive sensing signal andthe transcapacitive sensing signal. For example, one or more of thewaveform, amplitude, frequency, phase, and number of voltage transitionsof the active pen signal differs from that of the absolute capacitivesensing signal and the transcapacitive sensing signal. Further, one ormore of the parameters of the active pen signal (e.g., frequency,amplitude, phase, and duty cycle) may be varied to identify differentstates of the active pen. For example, the active pen may alter thefrequency of the active pen to indicate a change in a state of theactive pen. The different states of the active pen may identify an inputcolor, brush sizes/widths, tools (e.g., pencil, eraser), button press,and gesture inputs, among others.

The sensor circuitry 112 acquires the resulting signals during acapacitive frame. Further, during a capacitive frame, the sensorcircuitry 112 operates the sensor electrodes 120 for one or more oftranscapacitive sensing, absolute capacitive sensing, and active pensensing to acquire the resulting signals.

As illustrated in FIG. 1, the processing system 110 includes adetermination module 114. The determination module 114 is electricallyconnected to the sensor circuitry 112 and receives resulting signalsfrom the sensor circuitry 112. The determination module 114 processesthe resulting signals to determine changes in capacitance correspondingto one or more of the sensor electrodes 120 and/or parameters of anactive pen signal. For example, the determination module 114 processesthe resulting signals to determine changes in capacitance between one ormore of the sensor electrodes 120 and the input object 140. Such changesin capacitance may be referred to as changes in absolute capacitance.The determination module 114 determines positional information of theinput object 140 relative to the sensing region of the input device 100based on the changes in capacitance between the one or more sensorelectrodes 120 and the input object 140. For example, the determinationmodule 114 determines presence and/or absence of the input object 140based on the changes in capacitance between the one or more sensorelectrodes 120 and the input object 140. Further, the determinationmodule 114 determines a position (e.g., location) of an input object 140within a sensing region of the input device 100 on the changes incapacitance between the one or more sensor electrodes 120 and the inputobject 140.

The determination module 114 processes the resulting signals todetermine changes in a capacitance between two or more of the sensorelectrodes 120. Such changes of capacitance may be referred to aschanges transcapacitance or mutual capacitance. The determination module114 determines positional information for the input object 140 relativeto a sensing region of the input device 100 based on the changes incapacitance between two or more of the sensor electrodes 120. Further,the determination module 114 performs one or more correction algorithmson the changes in transcapacitance based on the changes in absolutecapacitance. For example, the determination module 114 removesinterference coupled by the input object 140 into the input device 100from the changes in transcapacitance based on the changes in absolutecapacitance. Additionally, or alternatively, when the input device 100is operating in a low ground mass state, the determination module 114adjusts the changes in transcapacitance based on the changes of absolutecapacitance. The input device 100 may be determined to be operating in alow ground mass state when the input device 100 does not have sufficientground (e.g., the input device 100 is on an insulated surface and notconnected to ground). Adjusting the changes in transcapacitancecomprises increasing and/or decreasing values according to the changesin transcapacitance based on the changes of absolute capacitance.

Additionally, or alternatively, the determination module 114 determinesparameters of an active pen signal. For example, the determinationmodule 114 determines positional information of the input object 140relative to the sensing region of the input device 100 based on thereceived active pen signal. Further, the determination module 114 maydetermines state information of the active pen based on the receivedactive pen signal.

“Positional information” as used herein broadly encompasses absoluteposition, relative position, velocity, acceleration, and other types ofspatial information. Exemplary “zero-dimensional” positional informationincludes near/far or contact/no contact information. Exemplary“one-dimensional” positional information includes positions along anaxis. Exemplary “two-dimensional” positional information includesmotions in a plane. Exemplary “three-dimensional” positional informationincludes instantaneous or average velocities in space. Further examplesinclude other representations of spatial information. Historical dataregarding one or more types of positional information may also bedetermined and/or stored, including, for example, historical data thattracks position, motion, or instantaneous velocity over time.

In one embodiment, the determination module 114 processes the resultingsignals by removing baseline measurements from the resulting signals.Baseline measurements compensate for a capacitive coupling between thesensor electrodes 120 and one or more nearby electrodes. The nearbyelectrodes may be display electrodes of a display device, unused sensorelectrodes, and/or other proximate conductive objects. For example, thebaseline measurements may account for display update signals (e.g.,display update signals, gate select and deselect signals, or emissioncontrol signals) of a display device capacitively coupled to the sensorelectrodes 120 via display electrodes of the display device. Removingthe baseline measurements from the resulting signals may comprisesubtracting the baseline measurements from the resulting signals orcompensating for the baseline measurements in other ways.

The determination module 114 determines a capacitive image. For example,the determination module 114 determines a set of measurements of changesin capacitance from the processed resulting signals, and forms acapacitive image from the set of measurements. Additionally, oralternatively, profiles along each axis of the sensor electrodes 120 maybe formed from the set of measurements. Successive capacitive imagesand/or profiles acquired over successive periods of time are used totrack the motion(s) of one or more input objects 140 entering, exiting,and/or moving within the sensing region of the input device 100.Further, during each capacitive frame one or more capacitive imagesand/or profiles may be determined from the resulting signals.Additionally, or alternatively, profiles and/or capacitive images may bedetermined from a set of measurements determined from the receivedactive pen signal. As is described above, in such embodiments,successive profiles and/or capacitive images are acquired oversuccessive period of time are used to track the motion of an active penentering, exiting, and/or moving within the sensing region of the inputdevice 100.

The sensor electrodes 120 include the sensor electrodes 120 a and 120 b.The sensor electrodes 120 a and 120 b are formed from a conductivematerial. Further, the sensor electrodes 120 a and 120 b may be formedfrom a conductive material that is at least substantially transparent.For example, the sensor electrodes 120 a and 120 b may be formed fromindium tin oxide (ITO), carbon nanotubes, or metal mesh, among others.

The sensor electrodes 120 form areas of localized capacitance. The areasof localized capacitance may correspond to capacitive pixels of acapacitive image. Capacitive pixels may be formed between an individualsensor electrode 120 and ground when the sensor electrodes 120 areoperated for absolute capacitive sensing. Further, the capacitivesensing pixels may be formed between sensor electrodes 120 when thesensor electrodes 120 are operated for transcapacitive sensing.

As illustrated, the plurality of sensor electrodes 120 are disposed as aplurality of non-overlapping rectangles. In other embodiments, one ormore of the sensor electrodes 120 a overlaps one or more of the sensorelectrodes 120 b. The sensor electrodes 120 a and 120 b have arectangular shape. However, in other embodiments, the sensor electrodes120 a and/or the sensor electrodes 120 b have other shapes. Asillustrated, the sensor electrodes 120 a differ in size (e.g., widthand/or length) from the sensor electrodes 120 b. In other embodiments,the sensor electrodes 120 a and 120 b may be similar in size (e.g., acommon width and/or length). Further, the shape of the sensor electrodes120 a may be the same or different from the shape of the sensorelectrodes 120 b.

The sensor electrodes 120 may be disposed in configurations other thanillustrated in FIG. 1. For example, the sensor electrodes 120 may bedisposed in polar arrays, repeating patterns, non-repeating patterns,non-uniform arrays, a single row or column, or other suitablearrangement. Further, the sensor electrodes 120 may be any shape such ascircular, rectangular, diamond, star, square, noncovex, convex,nonconcave, concave, etc. Further, the number of sensor electrodes 120may differ from what is illustrated in FIG. 1. For example, the numberof sensor electrodes 120 a may be greater than or less than thatillustrated in FIG. 1 and the number of sensor electrodes 120 b may begreater than or less than that illustrated in FIG. 1. Further, thenumber of sensor electrodes 120 a may be greater than, less than, orequal to the number of sensor electrodes 120 b.

The sensor electrodes 120 are electrically coupled to the processingsystem 110 via traces 150. As illustrated in FIG. 1, the traces 150 areelectrically connected to the sensor electrodes 120 b in an alternatingpattern. However, in other embodiments, the traces 150 may beelectrically connected to the sensor electrodes 120 b using otherpatterns.

In one or more embodiments, the sensor electrodes 120 a and 120 b may bedisposed in a common layer (e.g., a common side of a substrate). Forexample, the sensor electrodes 120 a and 120 b are disposed in anon-overlapping fashion. In one embodiment, one of the sensor electrodes120 a and 120 b include jumpers which cross over the other one of thesensor electrodes 120 a and 120 b.

In one or more embodiments, the sensor electrodes 120 a are disposed ona first layer and the sensor electrodes 120 b are disposed on a secondlayer different from the first layer. For example, in one embodiment,the sensor electrodes 120 a are disposed on a first side of a substrateand the sensor electrodes 120 b are disposed on a second side of thesubstrate. Alternatively, the sensor electrodes 120 a are disposed on afirst substrate and the sensor electrodes 120 b are disposed on a secondsubstrate.

FIG. 2 illustrates sensor electrodes 220 disposed in a pattern differentfrom that of the sensor electrodes 120. For example, the sensorelectrodes 220 are disposed such that one or more sensor electrodes 220overlaps another one or more of the sensor electrodes 220. Asillustrated, each of the sensor electrodes 220 a overlaps each of thesensor electrodes 220 b. The sensor electrodes 220 a and 220 b may bedisposed on different layers such that the sensor electrodes 220 aoverlap the sensor electrodes 220 b. For example, the sensor electrodes220 a may be disposed on a first side of a substrate and the sensorelectrodes 220 b may be disposed on a second side of the substrate.Alternatively, the sensor electrodes 220 a and 220 b may be disposed ondifferent substrates. The sensor electrodes 220 illustrate a differentembodiment of the sensor electrodes 120, and throughout this disclosure,the sensor electrodes 220 may be utilized interchangeable with thesensor electrodes 120. For example, the sensor electrodes 220 may becoupled to the processing system 110 via traces 150, such that thesensor electrodes 220 are operated for absolute capacitive sensing,transcapacitive sensing, and/or active pen sensing.

FIG. 3A illustrates an input device 300, according to one or moreembodiments. The input device 300 is configured similar to that of theinput device 100 of FIG. 1. For example, the input device 300 isconfigured to detect an input object (e.g., the input object 140) usingthe sensor electrodes 120. In other embodiment, the input device isconfigured to detect an input object using the sensor electrodes 220illustrated in FIG. 2 instead of the sensor electrodes 120. However, ascompared the input device 100, the input device 300 includes the displaydevice 302. The display device 302 is one of a liquid crystal display(LCD) device or an organic light emitting diode (OLED) display device,among others.

The display device 302 includes the display panel 320 having subpixels321. In embodiments where the display device 302 is an OLED displaydevice, each subpixel 321 is coupled to a gate line 322, a data line324, and an emission control line 326. In embodiments where the displaydevice 302 is an LCD device, the emission control lines 326 may beomitted, and each subpixel is couple to a gate line 322 and a data line324. Each subpixel 321 includes a pixel electrode and subpixelcircuitry. The subpixel circuitry may include one or more capacitorsand/or one or more transistors. The subpixel circuitry is configured toconnect and disconnect the pixel electrodes from corresponding ones ofthe data line 324 for updating of the subpixels 321.

The gate lines 322 are coupled to gate select circuitry 328 of thedisplay panel 320 and select (assert) and deselect (de-assert) subpixels321 for display updating. For example, the gate select circuitry 328 maybe configured to drive gate select and gate deselect signals onto thegate lines 322 to select and deselect the subpixels 321 for displayupdating. The gate select signals may be referred to as gate highsignals (V_(gh)) and gate deselect signals may be referred to as gatelow signals (V_(gl)). In such embodiments, V_(gh) may have a value in arange of about 10 V to about 15 V. Further, V_(gl) may have a value ofabout −5 V to 5 V. However, in other embodiments, other voltage valuesfor V_(gh) and/or V_(gl) may be utilized.

The gate select circuitry 328 drives a first gate line 322 with a gateselect signal to select each subpixel 321 coupled with the first gateline 322. Further, the gate select circuitry 328 drives a second gateline 322 with a gate deselect signal to deselect each subpixel coupledwith the second gate line 322. The gate select circuitry 328 may alsodrive each gate line 322 other than the gate line driven with the gateselect signal with the gate deselect signal. The gate select circuitry328 may include one or more shift registers configured to drive the gatelines 322 with the gate select signal and the gate deselect signal.

The processing system 310 includes sensor driver 311 and a displaydriver 312. The sensor driver 311 includes the sensor circuitry 112 andthe determination module 114, which are described in more detail withregard to FIG. 1.

The display driver 312 includes the display driver circuitry 314 that isconfigured to drive the data lines 324 with display update signals toupdate the subpixels 321. The display driver circuitry 314 comprises oneor more source drivers, digital to analog converters (DACs), andamplifiers, among other circuit elements. In such embodiments, eachsource driver may be coupled to one or more of the data lines 324 and isconfigured to drive the data lines 324 with display update signals toupdate the selected subpixels 321.

The subpixels 321 are driven for display updating during a displayframe. During a display frame, each of the subpixels 321 is driven witha respective display update signal to update the display panel 320.Display frames may occur at a display frame rate. Example display framerates may be 30 Hz, 60 Hz, 90 Hz, 120 Hz, 240 Hz, or 360 Hz. However,other display frame rates may be utilized. During each display frame,the subpixels 321 are updated display line by display line, such thatone display line is updated at a time. A display line corresponds to arow (or another grouping) of the subpixels 321 that are coupled to acommon gate line or lines 322. Further, the period of time that isutilized to update a display line may be referred to as a display lineupdate period. A display line update period may have a length of about 6μs to about 9 μs. However, the display line update period may have alength of less than 6 μs or greater than 9 μs.

FIG. 3B illustrates example drive blocks of a display frame 360. Asillustrated, the display frame 360 includes vertical blanking periods372, 374, and display update periods 382, 384, and 386. During thedisplay update periods 382, 384, and 386, the subpixels 321 are drivento update the display device 302. Further, while three display updateperiods are illustrated in the display frame 360, in other embodiments,other number of display update periods may be utilized. Further, thevertical blanking period 372 occurs at the beginning of the displayframe 360 (e.g., before each of the display update periods 382-386), andthe vertical blanking period 374 occurs at the end of the display frame360 (e.g., after each of the display update periods 382-386).

The display update periods 382-386 include one or more display lineupdate periods. For example, in one embodiment, the display line updateperiods may include a hundred or more display line update periods. Inother embodiments, the display update periods may include less than ormore than a hundred display line update periods. Each display lineupdate period includes an active subpixel drive period and a horizontalblanking period. During the active subpixel drive period, the selectedsubpixels 321 are driven by the display driver 312 with the displayupdate signals. During the horizontal blanking period, the subpixels 321are not actively driven. Further, during the horizontal blanking period,the current gate line 322 is deselected, a next gate line 322 isselected, and/or the display driver circuitry 314 is reconfigured todrive the display update signals for the next display line. The activesubpixel drive period is longer than the horizontal blanking time andmakes up a majority of the display line update period.

The length of the display update periods 382-386 may differ from eachother. For example, one or more of the display update periods 382-386may be longer than another one of the display update periods 382-386.Alternatively, each of the display update periods 382-386 may be thesame length.

The display update periods 382, 384, and 386 are separated from eachother by a long horizontal blanking period (e.g., the long horizontalblanking periods 392, 394). For example, the long horizontal blankingperiod 392 occurs between the display update periods 382 and 384 and thelong horizontal blanking period 394 occurs between the display updateperiods 384 and 386. While two long horizontal blanking periods areillustrated, in other embodiments, a display frame may include more orless than two long horizontal blanking periods.

The long horizontal blanking periods 392 and 394 are longer than adisplay line update period (e.g., the display line update period 362 ofFIG. 3C). Further, during the long horizontal blanking periods 392 and394, the display of the display panel 320 is not updated. For example,during the long horizontal blanking periods 392 and 394, the subpixels321 are not driven with display update signal for display updating.Accordingly, as the display of the display panel 320 is not beingupdated during the long horizontal blanking periods 392 and 394 and isbeing updated during the display update periods 382-386, the amount ofinterference emitted by the display device 302 during the longhorizontal blanking periods 392 and 394 is less than that emitting bythe display device 302 during the display update periods 382-386. In oneor more embodiments, the length, starting point, and/or ending point ofone or more of the long horizontal blanking periods 392 and 394 may beadjusted.

The vertical blanking periods 372 and 374 and the long horizontalblanking periods 392 and 394 may be referred to as non-display updateperiods as the subpixels 321 are not actively driven during theseperiods for updating the display device 302.

During the vertical blanking periods 372 and 374, the subpixels 321 arenot driven for updating the display device 302. In one embodiment, thelength of the vertical blanking periods may be adjusted to control thedisplay frame rate. Further, during the vertical blanking periods, thedisplay driver circuitry 314 of the display driver 312 may be configuredto update the display of the display panel 320 during the next displayframe.

In various embodiments, the number, order and length of the verticalblanking periods, display update periods, and/or the long horizontalblanking periods may vary between display frames.

In one or more embodiments, the display frame 360 is associated with oneor more capacitive frames. For example, in one embodiment, the displayframe 360 is associated with a single capacitive frame. In otherembodiments, the display frame 360 is associated with two or morecapacitive frames.

FIG. 3C illustrates an example display line update period 362. Thedisplay line update period 362 includes active subpixel drive period 363and horizontal blanking period 364. In one embodiment, the display lineupdate period 362 has a length about 9 μs, the active subpixel driveperiod 363 has a length of about 6 μs and the horizontal blanking periodhas a length of about 3 μs. Alternatively, the length of the displayline update period 362 may be less than or greater than 9 μs. Forexample, as the resolution and/or display update frequencies (e.g.,frames rates) increase, the length of the display line update period 362may be decreased. Further in various embodiments, the length of theactive pixel drive period may be greater than or less than 6 μs and/orthe length of the horizontal blanking period 364 may be less than orgreater than 3 μs.

With further reference to FIG. 3A, the display driver 312 receives imagedata from an external processor (e.g., a host processor or a timingcontroller) and generates the display update signals from the imagedata. Further, the display driver 312 generates one or more a displaycontrol signals from the image data. In other embodiments, the displaydriver 312 receives the display update signals and/or the controlsignals from the external processor.

The display control signals may include one or more pulses. In oneembodiment, the display control signals include one or more of ahorizontal sync signal (HSYNC), a vertical sync signal (VSYNC), dataenable signal, pixel clock signal, and/or a brightness control signal.HSYNC corresponds to the start of a display line update period and/or toan end of a display line update period. Further, HSYNC additionally, oralternatively, identifies one or more blanking periods that correspondto a display line update period. VSYNC corresponds to a start and/or anend of a display frame. Further, the VSYNC signal additionally, oralternatively, identifies one or more vertical blanking periods within adisplay frame. The display enable signal may be a composite signal ofboth the HSYNC and VSYNC signal, and identifies the start time of adisplay frame, an end time of a display frame, horizontal blankingperiods corresponding to a display line update period, and/or verticalblanking periods within a display frame.

The display driver 312 is electrically connected with the sensor driver311 via the communication path 316. In one embodiment, the displaydriver 312 transmits one or more display controls signals to the sensordriver 311 via the communication path 316.

The processing system 310 includes one or more integrated circuits (IC)chips. In one embodiment, the display driver 312 and the sensor driver311 are included within a common IC chip. In such embodiments, thecommunication path 316 is internal to the IC chip. In anotherembodiment, the display driver 312 is part of a first IC chip and thesensor driver 311 is part of a second IC chip. In such embodiments, thecommunication path 316 electrically connects the IC chips.

FIG. 4 is a cross-sectional view of a portion of the input device 300,according to one or more embodiments. As illustrated in FIG. 4, theinput device 300 includes a substrate 410, thin-film transistor (TFT)layers 420, the gate lines 322, the data lines 324, the emission controllines 326, a subpixel electrode layer 430, a display material layer 440,a reference electrode layer 450, display layers 460, an encapsulationlayer 470, and the sensor electrodes 120. In one or more embodiments,the emission control lines 326 may be omitted.

The substrate 410 is a rigid substrate or a flexible substrate. In oneembodiment, the substrate 410 is a plastic substrate. In otherembodiments, the substrate 410 is a glass substrate. The TFT layers 420include the subpixel circuit elements (e.g., transistors and capacitors)configured to control the selection, deselection, and driving of thesubpixels 321. The gate lines 322, data lines 324, and the emissioncontrol lines 326 are disposed in one or more metal layers on thesubstrate 410. For example, the gate lines 322 may be disposed in afirst metal layer, the data lines 324 may be disposed in a second metallayer, and the emission control lines 326 may be disposed in a thirdmetal layer. In other embodiments, the gate lines 322 and the emissioncontrol lines 326 are disposed in a common metal layer. The gate lines322 may be disposed in a metal layer above or below the metal layercomprising data lines 324 and/or the metal layer comprising the emissioncontrol lines 326. Alternatively, the data lines 324 may be disposed ina metal layer above or below the metal layer comprising gate lines 322and/or the metal layer comprising the emission control lines 326.

The subpixel electrode layer 430 comprises the subpixel electrodes ofeach subpixel 321. In embodiments where the display device 302 is anOLED display device, the subpixels electrodes are anode electrodes. Inembodiments where the display device 302 is an LCD device, the subpixelselectrodes comprise LCD subpixel electrodes. The subpixel electrodes maybe formed from indium tin oxide (ITO) or other suitable material.

As illustrated in FIG. 4, the display material layer 440 is disposedbetween the subpixel electrode layer 430 and the reference electrodelayer 450. However, in other embodiments, the display material layer 440may be disposed above the subpixel electrode layer 430 and the referenceelectrode layer 450. In embodiments where the display device 302 is anOLED display device, the display material layer 440 is an organicmaterial layer. Further, in such embodiments, the display material layer440 is disposed between the subpixel electrode layer 430 and thereference electrode layer 450. In embodiments where the display device302 is an LCD device, the display material layer 440 is a liquid crystalmaterial. In such embodiments, the display material layer 440 isdisposed between the subpixel electrode layer 430 and the referenceelectrode layer 450 or above the subpixel electrode layer 430 and thereference electrode layer 450.

The reference electrode layer 450 overlaps the subpixels electrodes ofthe subpixel electrode layer 430 and acts as a reference against whichthe subpixels of the subpixel electrode layer 430 are driven to updatethe subpixels 321. For example, the reference electrode layer 450 may bea cathode electrode layer or a common voltage (Vcom) electrode layer. Inembodiments where the display device 302 is an OLED display device, thereference electrode layer 450 is a cathode electrode. The cathodeelectrode is a sheet of resistive material. In one or more embodiment,the cathode electrode is a resistive sheet having a resistance of about1 to about 20 ohms per square. In one embodiment, the cathode electrodemay be comprised of a single electrode or multiple electrodes. Thecathode electrode is electrically connected with and driven by thedisplay driver 312 to supply a low impedance reference voltage againstwhich the subpixel electrodes of the subpixel electrode layer 430 aredriven.

In embodiments where the display device 302 is an LCD display device,the reference electrode layer 450 is a Vcom electrode layer. The Vcomelectrode layer may comprise one or more Vcom electrodes. The Vcomelectrode layer is electrically connected with and driven by the displaydriver 312 to supply a reference voltage against which the subpixelselectrodes of the subpixel electrode layer 430 are driven.

The display layers 460 may include one or more polarizers, one or moresubstrates, and/or a color filter glass, among others.

The encapsulation layer 470 is disposed over the other layers of thedisplay device 302. The encapsulation layer 470 may be rigid orflexible. Further, in one or more embodiments, the encapsulation layer470 may be omitted and a lens may be included instead. For example, inembodiments where the display panel 320 is an LCD display panel, theencapsulation layer 470 may be replaced with a lens disposed over thelayers of the display device 302. In one or more embodiments, a lens maybe included in addition to and over the encapsulation layer 470.

One or more of the sensor electrodes 120 may be disposed on theencapsulation layer 470. For example, one or more of the sensorelectrodes 120 is disposed on the encapsulation layer 470. In embodimentincluding a lens, one or more of the sensor electrodes 120 is disposedon the lens. Further, one or more of the sensor electrodes 120 may bedisposed on a substrate, or substrates, and adhered to the display panel320 (e.g., adhered to the encapsulation layer 470 or a lens). In oneembodiment, one or more sensor electrodes 120 are disposed on theencapsulation layer 470 or a lens, and a second one or more sensorelectrodes 120 are disposed on a substrate which is adhered to thedisplay panel 320.

FIG. 5 is a flowchart illustrating a method 500 for performing inputsensing, according one or more embodiments. At operation 510, the sensordriver 311 acquires first resulting signals from the sensor electrodes120. For example, the sensor driver 311 may operate the sensorelectrodes 120 for absolute capacitive sensing, transcapacitive sensing,and/or active pen sensing to receive the first resulting signals.

The operation 510 includes the operation 512, receiving a first displaycontrol signal. For example, at operation 512, the sensor driver 311receives a first display control signal indicative of a beginning of adisplay frame. In one embodiment, the first display control signal isindicative of a non-display update period (e.g., vertical blankingperiod or long horizontal blanking period) of a display frame.

With reference to FIG. 3A, a display control signal is communicated fromthe display driver 312 to the sensor driver 311 via the communicationpath 316 at the beginning of the display frame 360. The first displaycontrol signal may include one or more pulses. In one or moreembodiments, the first display signal may be a VSYNC signal or be basedon a VSYNC signal. Alternatively, the first display control signal maybe an HSYNC signal or based on an HSYNC signal.

The sensor driver 311, based on receipt of the first display controlsignal, initiates the acquisition of the first resulting signals. Forexample, the sensor driver 311 may initiate the acquisition of the firstresulting signals based on a pulse of the first display control signal.In one embodiment, initiating acquisition of the first resulting signalbased on the pulse of the first display control signal comprisesdetecting a rising edge of a pulse of the first display control signaland initiating acquisition of the first resulting signals based on thedetection of the rising edge of the pulse of the first display controlsignal. Initiating the acquisition of the first resulting signalscomprises operating the sensor electrodes 120 for transcapacitivesensing, absolute capacitive sensing, or active pen sensing.

In one embodiment, during operation 510, the sensor driver 311 operatesone or more of the sensor electrodes 120 for absolute capacitive sensingduring a period of time that overlaps with a non-display update periodof the display frame 360. For example, the sensor driver 311 operatesone or more of the sensor electrodes 120 for absolute capacitive sensingduring a period of time that overlaps with the vertical blanking period372 or the long horizontal blanking period 392. Operating one or more ofthe sensor electrodes 120 for absolute capacitive sensing includesoperating each of the sensor electrodes 120 for absolute capacitivesensing, operating each of the sensor electrodes 120 a or 120 b forabsolute capacitive sensing, or operating less than all of the sensorelectrodes 120 a or 120 b for absolute capacitive sensing. Further,operating one or more of the sensor electrodes 120 for absolutecapacitive sensing comprises driving the one or more of the sensorelectrodes 120 with an absolute capacitive sensing signal whilereceiving resulting signals with the driven one or more sensorelectrodes 120.

In one embodiment, during operation 510, the sensor driver 311 operatesone or more of the sensor electrodes 120 for transcapacitive sensingduring a period of time that overlaps with a non-display update periodof the display frame 360. For example, the sensor driver 311 operatestwo or more of the sensor electrodes 120 for transcapacitive sensingduring a period of time that overlaps with the vertical blanking period372 or the long horizontal blanking period 392. Operating one or more ofthe sensor electrodes 120 for transcapacitive sensing includes operatingeach of the sensor electrodes 120 for transcapacitive sensing, operatingeach of the sensor electrodes 120 a or 120 b for transcapacitivesensing, or operating less than all of the sensor electrodes 120 a or120 b for transcapacitive sensing. Further, operating one or more of thesensor electrodes 120 for transcapacitive sensing comprising driving afirst one or more of the sensor electrodes 120 with a transcapacitivesensing signal while receiving resulting signals with a second one ormore of the more sensor electrodes 120.

In one embodiment, during operation 510, the sensor driver 311 operatesone or more of the sensor electrodes 120 for active pen sensing during aperiod of time that overlaps with a non-display update period of thedisplay frame 360. For example, the sensor driver 311 operates one ormore of the sensor electrodes 120 for active pen sensing during a periodof time that overlaps with the vertical blanking period 372 or the longhorizontal blanking period 392. Operating one or more of the sensorelectrodes 120 for active pen sensing includes operating each of thesensor electrodes 120 for active pen sensing, operating each of thesensor electrodes 120 a or 120 b for active pen sensing, or operatingless than all of the sensor electrodes 120 a or 120 b for active pensensing. For example, operating one or more of the sensor electrodes 120for active pen sensing includes driving one or more of the sensorelectrodes 120 with a substantially constant voltage to receive theactive pens signal.

The operation 520 includes operation 522 which comprises receiving asecond display control signal. For example, at operation 522, the sensordriver 311 receives a second display control signal indicative of abeginning of a display update period of a display frame.

With reference to FIG. 3A, a second display control signal iscommunicated from the display driver 312 to the sensor driver 311 viathe communication path 316 at the beginning of the display update period382. The second display control signal may include one or more pulses.In one or more embodiments, the second display signal is a VSYNC signalor is based on a VSYNC signal. Alternatively, the second display controlsignal is an HSYNC signal or based on an HSYNC signal.

The sensor driver 311, based on receipt of the second display controlsignal, initiates the acquisition of the second resulting signals. Forexample, the sensor driver 311 initiates the acquisition of the secondresulting signals based on a pulse of the second display control signal.In one embodiment, initiating acquisition of the second resulting signalbased on the pulse of the second display control signal comprisesdetecting a rising edge of a pulse of the second display control signaland initiating acquisition of the second resulting signals based on thedetection of the rising edge of the pulse of the second display controlsignal. Further, initiating the acquisition of the second resultingsignals comprises operating the sensor electrodes 120 fortranscapacitive sensing, absolute capacitive sensing, or active pensensing.

In one embodiment, during operation 520, the sensor driver 311 operatesone or more of the sensor electrodes 120 for absolute capacitive sensingduring a period of time that overlaps with a display update period ofthe display frame 360.

In one embodiment during operation 520, the sensor driver 311 operatesone or more of the sensor electrodes 120 for transcapacitive sensingduring a period of time that overlaps with a display update period ofthe display frame 360.

In another embodiment during operation 520, the sensor driver 311operates one or more of the sensor electrodes 120 for active pen sensingduring a period of time that overlaps with a display update period ofthe display frame 360.

In one or more embodiments during operations 510 and 520, the sensordriver 311 operates the sensor electrodes 120 for a first type and asecond type of input sensing. For example, during operation 510, thesensor driver 311 operates the sensor electrodes 120 for absolutecapacitive sensing or active pen sensing, and during operation 520, thesensor driver 311 operates the sensor electrodes 120 for transcapacitivesensing.

The operation 530 includes operation 532 which comprises receiving athird display control signal. For example, at operation 532, the sensordriver 311 receives a third display control signal indicative of abeginning of a non-display update period of a display frame. In oneembodiment, the third display control signal is indicative of abeginning a long horizontal blanking period a display frame. Optionally,the operation 530 may be omitted from the method 500.

With reference to FIG. 3A, a third display control signal iscommunicated from the display driver 312 to the sensor driver 311 at thebeginning of the end of the display update period 382 or at thebeginning of a long horizontal blanking period 392. The third displaycontrol signal may include one or more pulses. In one or moreembodiments, the third display signal may be an HSYNC signal or based onan HSYNC signal.

The sensor driver 311, based on receipt of the third display controlsignal, initiates the acquisition of the third resulting signals. Forexample, the sensor driver 311 initiates the acquisition of the thirdresulting signals based on a pulse of the third display control signal.In one embodiment, initiating acquisition of the third resulting signalbased on the pulse of the third display control signal comprisesdetecting a rising edge of a pulse of the third display control signaland initiating acquisition of the third resulting signals based on thedetection of the rising edge of the pulse of the third display controlsignal. Further, initiating the acquisition of the third resultingsignals comprises operating the sensor electrodes 120 fortranscapacitive sensing, absolute capacitive sensing, or active pensensing.

In one embodiment during operation 530, the sensor driver 311 operatesone or more of the sensor electrodes 120 for absolute capacitive sensingduring a period of time that at least partially overlaps with the longhorizontal blanking period 392 of the display frame 360.

In other embodiments during operation 530, the sensor driver 311operates one or more of the sensor electrodes 120 for transcapacitivesensing during a period of time that at least partially overlaps withthe long horizontal blanking period 392 of the display frame 360.

In one or more embodiments during operation 530, the sensor driver 311operates one or more of the sensor electrodes 120 for active pen sensingduring a period of time that at least partially overlaps with the longhorizontal blanking period 392 of the display frame 360.

In various embodiments during operation 520, the sensor driver 311operates the sensor electrodes 120 for a first type of input sensingand, during operation 530, the sensor driver 311 operates the sensorelectrodes 120 for a second type of input sensing. For example, duringoperation 520, the sensor driver 311 operates the sensor electrodes 120for transcapacitive sensing, and, during operation 530, the sensordriver 311 operates the sensor electrodes 120 for absolute capacitivesensing or active pen sensing.

The operation 540 includes operation 542 which comprises receiving afourth display control signal. For example, at operation 542, the sensordriver 311 receives a fourth display control signal indicative of abeginning of a display update period of a display frame. In oneembodiment, the fourth display control signal is indicative of an end ofa non-display update period of a display frame. Optionally, theoperation 540 may be omitted from the method 500.

With reference to FIG. 3A, a fourth display control signal iscommunicated from the display driver 312 to the sensor driver 311 at thebeginning of the display update period 384. The fourth display controlsignal may include one or more pulses. In one or more embodiments, thefourth display signal is a VSYNC signal or is based on a VSYNC signal.Alternatively, the fourth display control signal is an HSYNC signal orbased on an HSYNC signal.

The sensor driver 311, based on receipt of the fourth display controlsignal, initiates the acquisition of the fourth resulting signals. Forexample, the sensor driver 311 initiates the acquisition of the fourthresulting signals based on a pulse of the fourth display control signal.In one embodiment, initiating acquisition of the fourth resulting signalbased on the pulse of the fourth display control signal comprisesdetecting a rising edge of a pulse of the fourth display control signaland initiating acquisition of the fourth resulting signals based on thedetection of the rising edge of the pulse of the fourth display controlsignal. Further, initiating the acquisition of the fourth resultingsignals comprises operating one or more of the sensor electrodes 120 fortranscapacitive sensing, absolute capacitive sensing, or active pensensing.

In one embodiment during operation 540, the sensor driver 311 operatesone or more of the sensor electrodes 120 for absolute capacitive sensingduring a period of time that overlaps with the display update period 384of the display frame 360.

In one or more embodiments during operation 540, the sensor driver 311operates one or more of the sensor electrodes 120 for transcapacitivesensing during a period of time that overlaps with the display updateperiod of the display frame 360.

In various embodiments during operation 540, the sensor driver 311operates one or more of the sensor electrodes 120 for active pen sensingduring a period of time that overlaps with the display update period 384of the display frame 360.

During operations 520 and 540, the sensor driver 311 operates the sensorelectrodes 120 for the same type of input sensing. For example, thesensor driver 311 operates the sensor electrodes 120 for transcapacitivesensing during operations 520 and 540. Further, the sensor driver 311operates the sensor electrodes 120 for absolute capacitive sensingand/or active pen sensing during operations 520 and 540.

At operation 550, the determination module 114 determines positionalinformation for one or more input objects (e.g., the input object 140)based on one or more of the first, second, third, and fourth resultingsignals. For example, the determination module 114 determines changes incapacitance between the sensor electrodes 120 and/or between the sensorelectrodes 120 and the input object 140 and/or parameters of an activepens signal from the first, second, third, and fourth resulting signals.

In one or more embodiments, the determination module 114 compares two ormore of the first, second, third, and fourth resulting signals todetermine positional information for one or more input objects 140. Forexample, in embodiments where absolute capacitive sensing is performedduring the operation 510 and transcapacitive sensing is performed duringoperation 520, the determination module 114 compares the first resultingsignals with the second resulting signals to determine positionalinformation for the input object 140. In such embodiments, the firstresulting signals may be received during a period of time free frominterference due to updating the display device. Further in suchembodiments, the second resulting signals are received during a periodof time when interference due to updating the display is present.Accordingly, the first resulting signals is utilized to mitigateinterference within the second resulting signals. For example, the firstresulting signals is utilized to confirm the detection of one or moreinput objects detecting using the second resulting signals. In otherexamples, other interference mitigation techniques may be performedbased on the first and second resulting signals.

Further, the determination module 114 determines first positionalinformation from the first resulting signals and second positionalinformation from the second resulting signals. The determination module114 compares the first and a second positional information to mitigateinterference within the second positional information. For example, thefirst positional information is compared against the second positionalinformation to determine whether or not detected input objects in thesecond positional information are valid. Non-valid input objects may bereferred to as ghost input objects.

Ghost input objects refer to the incorrect determination of inputobjects within the sensing region of the input device (e.g., the inputdevice 100). The presence of ghost input objects may be caused by theeffects of display interference on the second resulting signals.However, as the first resulting signals are free from displayinterference, the first resulting signals (or positional informationdetermined from the first resulting signals) may be used to detectwhether or not ghost input objects exist in the second resulting signals(or positional information determined from the second resulting signals)based on a comparison of the first and second resulting signals (orpositional information determined form the first and second resultingsignals). If the number of and location of input objects identified bythe resulting signals (or the positional information determined from thefirst resulting signals) corresponds to the number of and location ofinput objects identified by the second resulting signals (or thepositional information generated from the second resulting signals), thesecond resulting signals (or the positional information determined fromthe second resulting signals) is determined to be valid and/orassociated with a high confidence value. The confidence valuecorresponds to the likelihood that each identified input object is avalid input object (e.g., a valid detection of an input object).However, if the number of and location of input objects identified bythe first resulting signals (or positional information determined fromthe first resulting signals) does corresponds to the number of andlocation of input objects identified by the second resulting signals (orpositional information determined from the second resulting signals),the second resulting signals (or positional information determined fromthe second resulting signals) is determined to not be valid and/orassociated with a low confidence value. Accordingly, the secondresulting signals may undergo additional filtering by the determinationmodule 114 or may be ignored.

In various embodiments, the first and second resulting signals may referto a first capacitive frame and the third and fourth resulting signalrefer to a second capacitive frame. In such an embodiment, the thirdresulting signals may be utilized to confirm the positional informationof input objects in the fourth resulting signals similar to how thefirst resulting signals may be utilized to confirm the positionalinformation of input objects in the second resulting signals.

In embodiments where active pen sensing is performed during theoperations 510 and/or 530, the determination module 114 determinespositional information for the active pen based on the first and/orthird resulting signals. In one embodiment, the determination module 114determines duty cycle of the active pen signal from the first and/orthird resulting signals and adjusts a corresponding non-display updatetime based on the duty cycle. For example, the determination module 114may alter a starting point for subsequent long horizontal blankingperiod (e.g., the long horizontal blanking period 394 within the displayframe 360 or a long horizontal blanking period of a subsequent displayframe) based on the third resulting signals. In one embodiment, alteringthe starting point for the long horizontal blanking period 394 comprisesinstructing the display driver 312 to start the long horizontal blankingperiod 394 earlier or later within the display frame 360. Alternatively,the length of a subsequent long horizontal blanking period (e.g., thelong horizontal blanking period 394 within the display frame 360 or along horizontal blanking period of a subsequent display frame) may beincreased or decreased based on the duty cycle of the active pen signaldetermined from the third resulting signals.

In one or more embodiments, the determination module 114 detects one ormore input objects in a sensing region of an input device, but not incontact with an input surface of the input device 100 based on the firstand/or third resulting signals. For example, in embodiments where thefirst and/or third resulting signals are acquired using absolutecapacitive sensing, the determination module 114 determinescorresponding first and/or third positional information from the firstand/or third resulting signals. In such embodiments, the first and/orthird positional information may be utilized to detect an input objectwithin the sensing region of an input device, but not in contact withthe input device. Further, in such embodiments, the first and/or thirdresulting signals may be utilized to detect an input object entering orleaving the sensing region of the input device.

Thus, the embodiments and examples set forth herein were presented toexplain the present technology and applications, and to enable thoseskilled in the art to make and use the disclosure. However, thoseskilled in the art will recognize that the foregoing description andexamples have been presented for the purposes of illustration andexample only. The description as set forth is not intended to beexhaustive or to limit the disclosure to the precise form disclosed.

In view of the foregoing, the scope of the present disclosure isdetermined by the claims that follow.

What is claimed is:
 1. A processing system comprising: a sensor driverconfigured to: receive a first display control signal corresponding to anon-display update period of a display frame and a second displaycontrol signal corresponding to a display update period of the displayframe; acquire, based on receipt of the first display control signal,first resulting signals from sensor electrodes electrically connected tothe sensor driver by operating the sensor electrodes for a first type ofinput sensing during a first period, wherein the first period overlapswith at least a portion of the non-display update period; and acquire,based on receipt of the second display control signal, second resultingsignals with the sensor electrodes by operating the sensor electrodesfor a second type of input sensing during a second period, wherein thesecond period overlaps with at least a portion of the display updateperiod, and wherein the second type of input sensing differs from thefirst type of input sensing.
 2. The processing system of claim 1,wherein operating the sensor electrodes for the first type of inputsensing comprises driving one or more of the sensor electrodes with anabsolute capacitive sensing signal and receiving the first resultingsignals with the driven one or more sensor electrodes.
 3. The processingsystem of claim 2, wherein operating the sensor electrodes for thesecond type of input sensing comprises driving a second one or more ofthe sensor electrodes with a transcapacitive sensing signal andreceiving the second resulting signals with a third one or more of thesensor electrodes.
 4. The processing system of claim 1, whereinoperating the sensor electrodes for the first type of input sensingcomprises operating a first one or more of the sensor electrodes foractive pen sensing.
 5. The processing system of claim 1 furthercomprising a determination module configured to mitigate interferencebased on a comparison of first positional information determined fromthe first resulting signals and second positional information determinedfrom the second resulting signals.
 6. The processing system of claim 5,wherein mitigating the interference comprises determining a validdetection of an input object.
 7. The processing system of claim 1,wherein the sensor driver is further configured to receive a thirddisplay control signal corresponding to a second non-display updateperiod of the display frame, wherein a timing of the third displaycontrol signal is adjusted at least partially based on the firstresulting signals.
 8. A method for input sensing comprising: receiving,at a sensor driver, a first display control signal corresponding to anon-display update period of a display frame and a second displaycontrol signal corresponding to a display update period of the displayframe; acquiring, based on receipt of the first display control signal,first resulting signals with sensor electrodes by operating the sensorelectrodes for a first type of input sensing during a first period,wherein the first period overlaps with at least a portion of thenon-display update period; and acquiring, based on receipt of the seconddisplay control signal, second resulting signals with the sensorelectrodes by operating the sensor electrodes for a second type of inputsensing during a second period, wherein the second period overlaps withat least a portion of the display update period, and wherein the secondtype of input sensing differs from the first type of input sensing. 9.The method of claim 8, wherein operating the sensor electrodes for thefirst type of input sensing comprises driving one or more of the sensorelectrodes with an absolute capacitive sensing signal and receiving thefirst resulting signals with the driven one or more sensor electrodes.10. The method of claim 9, wherein operating the sensor electrodes forthe second type of input sensing comprises driving a second one or moreof the sensor electrodes with a transcapacitive sensing signal andreceiving the second resulting signals with a third one or more of thesensor electrodes.
 11. The method of claim 8, wherein operating thesensor electrodes for the first type of input sensing comprisesoperating a first one or more of the sensor electrodes for active pensensing.
 12. The method of claim 8, mitigating interference based on acomparison of first positional information determined from the firstresulting signals and second positional information determined from thesecond resulting signals.
 13. The method of claim 12, wherein mitigatingthe interference comprises determining a valid detection of an inputobject.
 14. An input device comprising: sensor electrodes; and aprocessing system electrically connected to the sensor electrodes andconfigured to: receive a first display control signal corresponding to anon-display update period of a display frame and a second displaycontrol signal corresponding to a display update period of the displayframe; acquire, based on receipt of the first display control signal,first resulting signals with the sensor electrodes by operating thesensor electrodes for a first type of input sensing during a firstperiod, wherein the first period overlaps with at least a portion of thenon-display update period; and acquire, based on receipt of the seconddisplay control signal, second resulting signals with the sensorelectrodes by operating the sensor electrodes for a second type of inputsensing during a second period, wherein the second period overlaps withat least a portion of the display update period, and wherein the secondtype of input sensing differs from the first type of input sensing. 15.The input device of claim 14, wherein operating the sensor electrodesfor the first type of input sensing comprises driving one or more of thesensor electrodes with an absolute capacitive sensing signal andreceiving the first resulting signals with the driven one or more sensorelectrodes.
 16. The input device of claim 15, wherein operating thesensor electrodes for the second type of input sensing comprises drivinga second one or more of the sensor electrodes with a transcapacitivesensing signal and receiving the second resulting signals with a thirdone or more of the sensor electrodes.
 17. The input device of claim 14,wherein operating the sensor electrodes for the first type of inputsensing comprises operating a first one or more of the sensor electrodesfor active pen sensing.
 18. The input device of claim 14, wherein theprocessing system is further configured to mitigate interference basedon a comparison of first positional information determined from thefirst resulting signals and second positional information determinedfrom the second resulting signals.
 19. The input device of claim 18,wherein mitigating the interference comprises determining a validdetection of an input object.
 20. The input device of claim 14, furthercomprising a display device comprising display electrodes, wherein theprocessing system is configured to drive the display electrodes toupdate the display electrodes during the display update period.